The Huawei P9 Plus separates the audio playback – exactly like the HTC 10, too – over two different speakers. The first is a tweeter on the front, the second a woofer in the lower edge for mids and basses. The following Sound-Check video gives you the possibility to listen to the mono and stereo sound of the P9 Plus, and compares in with the (mono only) sound of the HTC 10: